Module: ActionView::Helpers::FormOptionsHelper

Includes:
TextHelper
Included in:
ActionView::Helpers, Tags::Base
Defined in:
lib/action_view/helpers/form_options_helper.rb

Overview

Provides a number of methods for turning different kinds of containers into a set of option tags.

The collection_select, select and time_zone_select methods take an options parameter, a hash:

  • :include_blank - set to true or a prompt string if the first option element of the select element is a blank. Useful if there is not a default value required for the select element.

    select("post", "category", Post::CATEGORIES, {include_blank: true})

    could become:

    Another common case is a select tag for a belongs_to-associated object.

    Example with @post.person_id => 2:

    select("post", "person_id", Person.all.collect {|p| [ p.name, p.id ] }, {include_blank: 'None'})

    could become:

  • :prompt - set to true or a prompt string. When the select element doesn't have a value yet, this prepends an option with a generic prompt -- "Please select" -- or the given prompt string.

    select("post", "person_id", Person.all.collect {|p| [ p.name, p.id ] }, {prompt: 'Select Person'})

    could become:

  • :index - like the other form helpers, select can accept an :index option to manually set the ID used in the resulting output. Unlike other helpers, select expects this option to be in the html_options parameter.

    select("album[]", "genre", %w[rap rock country], {}, { index: nil })

    becomes:

  • :disabled - can be a single value or an array of values that will be disabled options in the final output.

    select("post", "category", Post::CATEGORIES, {disabled: 'restricted'})

    could become:

    When used with the collection_select helper, :disabled can also be a Proc that identifies those options that should be disabled.

    collection_select(:post, :category_id, Category.all, :id, :name, {disabled: lambda{|category| category.archived? }})

    If the categories "2008 stuff" and "Christmas" return true when the method archived? is called, this would return:

Constant Summary

Constants included from TagHelper

TagHelper::BOOLEAN_ATTRIBUTES, TagHelper::PRE_CONTENT_STRINGS, TagHelper::TAG_PREFIXES

Instance Method Summary collapse

Methods included from TextHelper

#concat, #current_cycle, #cycle, #excerpt, #highlight, #pluralize, #reset_cycle, #safe_concat, #simple_format, #truncate, #word_wrap

Methods included from OutputSafetyHelper

#raw, #safe_join

Methods included from TagHelper

#cdata_section, #content_tag, #escape_once, #tag

Methods included from CaptureHelper

#capture, #content_for, #content_for?, #provide, #with_output_buffer

Methods included from SanitizeHelper

#sanitize, #sanitize_css, #strip_links, #strip_tags

Instance Method Details

#collection_check_boxes(object, method, collection, value_method, text_method, options = {}, html_options = {}, &block) ⇒ Object

Returns check box tags for the collection of existing return values of method for +object+'s class. The value returned from calling method on the instance object will be selected. If calling method returns nil, no selection is made.

The :value_method and :text_method parameters are methods to be called on each member of collection. The return values are used as the value attribute and contents of each check box tag, respectively. They can also be any object that responds to call, such as a proc, that will be called for each member of the collection to retrieve the value/text.

Example object structure for use with this method: class Post < ActiveRecord::Base has_and_belongs_to_many :authors end class Author < ActiveRecord::Base has_and_belongs_to_many :posts def name_with_initial "#ActionView::Helpers::FormOptionsHelper.first_namefirst_name.first. #last_name" end end

Sample usage (selecting the associated Author for an instance of Post, @post): collection_check_boxes(:post, :author_ids, Author.all, :id, :name_with_initial)

If @post.author_ids is already [1], this would return:

It is also possible to customize the way the elements will be shown by giving a block to the method: collection_check_boxes(:post, :author_ids, Author.all, :id, :name_with_initial) do |b| b.label { b.check_box } end

The argument passed to the block is a special kind of builder for this collection, which has the ability to generate the label and check box for the current item in the collection, with proper text and value. Using it, you can change the label and check box display order or even use the label as wrapper, as in the example above.

The builder methods label and check_box also accept extra HTML options: collection_check_boxes(:post, :author_ids, Author.all, :id, :name_with_initial) do |b| b.label(class: "check_box") { b.check_box(class: "check_box") } end

There are also three special methods available: object, text and value, which are the current item being rendered, its text and value methods, respectively. You can use them like this: collection_check_boxes(:post, :author_ids, Author.all, :id, :name_with_initial) do |b| b.label(:"data-value" => b.value) { b.check_box + b.text } end



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# File 'lib/action_view/helpers/form_options_helper.rb', line 710

def collection_check_boxes(object, method, collection, value_method, text_method, options = {}, html_options = {}, &block)
  Tags::CollectionCheckBoxes.new(object, method, self, collection, value_method, text_method, options, html_options).render(&block)
end

#collection_radio_buttons(object, method, collection, value_method, text_method, options = {}, html_options = {}, &block) ⇒ Object

Returns radio button tags for the collection of existing return values of method for +object+'s class. The value returned from calling method on the instance object will be selected. If calling method returns nil, no selection is made.

The :value_method and :text_method parameters are methods to be called on each member of collection. The return values are used as the value attribute and contents of each radio button tag, respectively. They can also be any object that responds to call, such as a proc, that will be called for each member of the collection to retrieve the value/text.

Example object structure for use with this method: class Post < ActiveRecord::Base belongs_to :author end class Author < ActiveRecord::Base has_many :posts def name_with_initial "#ActionView::Helpers::FormOptionsHelper.first_namefirst_name.first. #last_name" end end

Sample usage (selecting the associated Author for an instance of Post, @post): collection_radio_buttons(:post, :author_id, Author.all, :id, :name_with_initial)

If @post.author_id is already 1, this would return:

It is also possible to customize the way the elements will be shown by giving a block to the method: collection_radio_buttons(:post, :author_id, Author.all, :id, :name_with_initial) do |b| b.label { b.radio_button } end

The argument passed to the block is a special kind of builder for this collection, which has the ability to generate the label and radio button for the current item in the collection, with proper text and value. Using it, you can change the label and radio button display order or even use the label as wrapper, as in the example above.

The builder methods label and radio_button also accept extra HTML options: collection_radio_buttons(:post, :author_id, Author.all, :id, :name_with_initial) do |b| b.label(class: "radio_button") { b.radio_button(class: "radio_button") } end

There are also three special methods available: object, text and value, which are the current item being rendered, its text and value methods, respectively. You can use them like this: collection_radio_buttons(:post, :author_id, Author.all, :id, :name_with_initial) do |b| b.label(:"data-value" => b.value) { b.radio_button + b.text } end



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# File 'lib/action_view/helpers/form_options_helper.rb', line 647

def collection_radio_buttons(object, method, collection, value_method, text_method, options = {}, html_options = {}, &block)
  Tags::CollectionRadioButtons.new(object, method, self, collection, value_method, text_method, options, html_options).render(&block)
end

#collection_select(object, method, collection, value_method, text_method, options = {}, html_options = {}) ⇒ Object

Returns 



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# File 'lib/action_view/helpers/form_options_helper.rb', line 201

def collection_select(object, method, collection, value_method, text_method, options = {}, html_options = {})
  Tags::CollectionSelect.new(object, method, self, collection, value_method, text_method, options, html_options).render
end

#grouped_collection_select(object, method, collection, group_method, group_label_method, option_key_method, option_value_method, options = {}, html_options = {}) ⇒ Object

Returns 



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# File 'lib/action_view/helpers/form_options_helper.rb', line 257

def grouped_collection_select(object, method, collection, group_method, group_label_method, option_key_method, option_value_method, options = {}, html_options = {})
  Tags::GroupedCollectionSelect.new(object, method, self, collection, group_method, group_label_method, option_key_method, option_value_method, options, html_options).render
end

#grouped_options_for_select(grouped_options, selected_key = nil, options = {}) ⇒ Object

Returns a string of tags, like options_for_select, but wraps them with tags:

grouped_options = [
['North America',
 [['United States','US'],'Canada']],
['Europe',
 ['Denmark','Germany','France']]
]
grouped_options_for_select(grouped_options)

grouped_options = {
'North America' => [['United States','US'], 'Canada'],
'Europe' => ['Denmark','Germany','France']
}
grouped_options_for_select(grouped_options)

Possible output:

Parameters:

  • grouped_options - Accepts a nested array or hash of strings. The first value serves as the label while the second value must be an array of options. The second value can be a nested array of text-value pairs. See options_for_select for more info. Ex. ["North America",[["United States","US"],["Canada","CA"]]]
  • selected_key - A value equal to the value attribute for one of the tags, which will have the selected attribute set. Note: It is possible for this value to match multiple options as you might have the same option in multiple groups. Each will then get selected="selected".

Options:

  • :prompt - set to true or a prompt string. When the select element doesn't have a value yet, this prepends an option with a generic prompt - "Please select" - or the given prompt string.

  • :divider - the divider for the options groups.

    grouped_options = [
[['United States','US'], 'Canada'],
['Denmark','Germany','France']
]
grouped_options_for_select(grouped_options, nil, divider: '---------')

    Possible output:

Note: Only the and tags are returned, so you still have to wrap the output in an appropriate tag.



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# File 'lib/action_view/helpers/form_options_helper.rb', line 454

def option_groups_from_collection_for_select(collection, group_method, group_label_method, option_key_method, option_value_method, selected_key = nil)
  collection.map do |group|
    option_tags = options_from_collection_for_select(
      group.send(group_method), option_key_method, option_value_method, selected_key)

    content_tag(:optgroup, option_tags, label: group.send(group_label_method))
  end.join.html_safe
end

#options_for_select(container, selected = nil) ⇒ Object

Accepts a container (hash, array, enumerable, your type) and returns a string of option tags. Given a container where the elements respond to first and last (such as a two-element array), the "lasts" serve as option values and the "firsts" as option text. Hashes are turned into this form automatically, so the keys become "firsts" and values become lasts. If selected is specified, the matching "last" or element will get the selected option-tag. selected may also be an array of values to be selected when using a multiple select.

options_for_select([["Dollar", "$"], ["Kroner", "DKK"]])
# => <option value="$">Dollar</option>
# => <option value="DKK">Kroner</option>

options_for_select([ "VISA", "MasterCard" ], "MasterCard")
# => <option>VISA</option>
# => <option selected="selected">MasterCard</option>

options_for_select({ "Basic" => "$20", "Plus" => "$40" }, "$40")
# => <option value="$20">Basic</option>
# => <option value="$40" selected="selected">Plus</option>

options_for_select([ "VISA", "MasterCard", "Discover" ], ["VISA", "Discover"])
# => <option selected="selected">VISA</option>
# => <option>MasterCard</option>
# => <option selected="selected">Discover</option>

You can optionally provide HTML attributes as the last element of the array.

options_for_select([ "Denmark", ["USA", {class: 'bold'}], "Sweden" ], ["USA", "Sweden"])
# => <option value="Denmark">Denmark</option>
# => <option value="USA" class="bold" selected="selected">USA</option>
# => <option value="Sweden" selected="selected">Sweden</option>

options_for_select([["Dollar", "$", {class: "bold"}], ["Kroner", "DKK", {onclick: "alert('HI');"}]])
# => <option value="$" class="bold">Dollar</option>
# => <option value="DKK" onclick="alert('HI');">Kroner</option>

If you wish to specify disabled option tags, set selected to be a hash, with :disabled being either a value or array of values to be disabled. In this case, you can use :selected to specify selected option tags.

options_for_select(["Free", "Basic", "Advanced", "Super Platinum"], disabled: "Super Platinum")
# => <option value="Free">Free</option>
# => <option value="Basic">Basic</option>
# => <option value="Advanced">Advanced</option>
# => <option value="Super Platinum" disabled="disabled">Super Platinum</option>

options_for_select(["Free", "Basic", "Advanced", "Super Platinum"], disabled: ["Advanced", "Super Platinum"])
# => <option value="Free">Free</option>
# => <option value="Basic">Basic</option>
# => <option value="Advanced" disabled="disabled">Advanced</option>
# => <option value="Super Platinum" disabled="disabled">Super Platinum</option>

options_for_select(["Free", "Basic", "Advanced", "Super Platinum"], selected: "Free", disabled: "Super Platinum")
# => <option value="Free" selected="selected">Free</option>
# => <option value="Basic">Basic</option>
# => <option value="Advanced">Advanced</option>
# => <option value="Super Platinum" disabled="disabled">Super Platinum</option>

NOTE: Only the option tags are returned, you have to wrap this call in a regular HTML select tag.



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# File 'lib/action_view/helpers/form_options_helper.rb', line 350

def options_for_select(container, selected = nil)
  return container if String === container

  selected, disabled = extract_selected_and_disabled(selected).map do |r|
    Array(r).map { |item| item.to_s }
  end

  container.map do |element|
    html_attributes = option_html_attributes(element)
    text, value = option_text_and_value(element).map { |item| item.to_s }

    html_attributes[:selected] ||= option_value_selected?(value, selected)
    html_attributes[:disabled] ||= disabled && option_value_selected?(value, disabled)
    html_attributes[:value] = value

    content_tag_string(:option, text, html_attributes)
  end.join("\n").html_safe
end

#options_from_collection_for_select(collection, value_method, text_method, selected = nil) ⇒ Object

Returns a string of option tags that have been compiled by iterating over the collection and assigning the result of a call to the value_method as the option value and the text_method as the option text.

options_from_collection_for_select(@people, 'id', 'name')
# => <option value="#{person.id}">#{person.name}</option>

This is more often than not used inside a #select_tag like this example:

select_tag 'person', options_from_collection_for_select(@people, 'id', 'name')

If selected is specified as a value or array of values, the element(s) returning a match on value_method will be selected option tag(s).

If selected is specified as a Proc, those members of the collection that return true for the anonymous function are the selected values.

selected can also be a hash, specifying both :selected and/or :disabled values as required.

Be sure to specify the same class as the value_method when specifying selected or disabled options. Failure to do this will produce undesired results. Example: options_from_collection_for_select(@people, 'id', 'name', '1') Will not select a person with the id of 1 because 1 (an Integer) is not the same as '1' (a string) options_from_collection_for_select(@people, 'id', 'name', 1) should produce the desired results.



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# File 'lib/action_view/helpers/form_options_helper.rb', line 393

def options_from_collection_for_select(collection, value_method, text_method, selected = nil)
  options = collection.map do |element|
    [value_for_collection(element, text_method), value_for_collection(element, value_method), option_html_attributes(element)]
  end
  selected, disabled = extract_selected_and_disabled(selected)
  select_deselect = {
    selected: extract_values_from_collection(collection, value_method, selected),
    disabled: extract_values_from_collection(collection, value_method, disabled)
  }

  options_for_select(options, select_deselect)
end

#select(object, method, choices = nil, options = {}, html_options = {}, &block) ⇒ Object

Create a select tag and a series of contained option tags for the provided object and method. The option currently held by the object will be selected, provided that the object is available.

There are two possible formats for the choices parameter, corresponding to other helpers' output:

  • A flat collection (see options_for_select).

  • A nested collection (see grouped_options_for_select).

For example:

select("post", "person_id", Person.all.collect {|p| [ p.name, p.id ] }, { include_blank: true })

would become:

assuming the associated person has ID 1.

This can be used to provide a default set of options in the standard way: before rendering the create form, a new model instance is assigned the default options and bound to @model_name. Usually this model is not saved to the database. Instead, a second model object is created when the create request is received. This allows the user to submit a form page more than once with the expected results of creating multiple records. In addition, this allows a single partial to be used to generate form inputs for both edit and create forms.

By default, post.person_id is the selected option. Specify selected: value to use a different selection or selected: nil to leave all options unselected. Similarly, you can specify values to be disabled in the option tags by specifying the :disabled option. This can either be a single value or an array of values to be disabled.

A block can be passed to select to customize how the options tags will be rendered. This is useful when the options tag has complex attributes.

select(report, "campaign_ids") do
available_campaigns.each do |c|
  content_tag(:option, c.name, value: c.id, data: { tags: c.tags.to_json })
end
end

Gotcha

The HTML specification says when multiple parameter passed to select and all options got deselected web browsers do not send any value to server. Unfortunately this introduces a gotcha: if an User model has many roles and have role_ids accessor, and in the form that edits roles of the user the user deselects all roles from role_ids multiple select box, no role_ids parameter is sent. So, any mass-assignment idiom like

@user.update(params[:user])

wouldn't update roles.

To prevent this the helper generates an auxiliary hidden field before every multiple select. The hidden field has the same name as multiple select and blank value.

Note: The client either sends only the hidden field (representing the deselected multiple select box), or both fields. This means that the resulting array always contains a blank string.

In case if you don't want the helper to generate this hidden field you can specify include_hidden: false option.



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# File 'lib/action_view/helpers/form_options_helper.rb', line 162

def select(object, method, choices = nil, options = {}, html_options = {}, &block)
  Tags::Select.new(object, method, self, choices, options, html_options, &block).render
end

#time_zone_options_for_select(selected = nil, priority_zones = nil, model = ::ActiveSupport::TimeZone) ⇒ Object

Returns a string of option tags for pretty much any time zone in the world. Supply a ActiveSupport::TimeZone name as selected to have it marked as the selected option tag. You can also supply an array of ActiveSupport::TimeZone objects as priority_zones, so that they will be listed above the rest of the (long) list. (You can use ActiveSupport::TimeZone.us_zones as a convenience for obtaining a list of the US time zones, or a Regexp to select the zones of your choice)

The selected parameter must be either nil, or a string that names a ActiveSupport::TimeZone.

By default, model is the ActiveSupport::TimeZone constant (which can be obtained in Active Record as a value object). The only requirement is that the model parameter be an object that responds to all, and returns an array of objects that represent time zones.

NOTE: Only the option tags are returned, you have to wrap this call in a regular HTML select tag.



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# File 'lib/action_view/helpers/form_options_helper.rb', line 568

def time_zone_options_for_select(selected = nil, priority_zones = nil, model = ::ActiveSupport::TimeZone)
  zone_options = "".html_safe

  zones = model.all
  convert_zones = lambda { |list| list.map { |z| [ z.to_s, z.name ] } }

  if priority_zones
    if priority_zones.is_a?(Regexp)
      priority_zones = zones.select { |z| z =~ priority_zones }
    end

    zone_options.safe_concat options_for_select(convert_zones[priority_zones], selected)
    zone_options.safe_concat content_tag(:option, '-------------', value: '', disabled: true)
    zone_options.safe_concat "\n"

    zones = zones - priority_zones
  end

  zone_options.safe_concat options_for_select(convert_zones[zones], selected)
end

#time_zone_select(object, method, priority_zones = nil, options = {}, html_options = {}) ⇒ Object

Returns select and option tags for the given object and method, using #time_zone_options_for_select to generate the list of option tags.

In addition to the :include_blank option documented above, this method also supports a :model option, which defaults to ActiveSupport::TimeZone. This may be used by users to specify a different time zone model object. (See time_zone_options_for_select for more information.)

You can also supply an array of ActiveSupport::TimeZone objects as priority_zones, so that they will be listed above the rest of the (long) list. (You can use ActiveSupport::TimeZone.us_zones as a convenience for obtaining a list of the US time zones, or a Regexp to select the zones of your choice)

Finally, this method supports a :default option, which selects a default ActiveSupport::TimeZone if the object's time zone is nil.

time_zone_select( "user", "time_zone", nil, include_blank: true)

time_zone_select( "user", "time_zone", nil, default: "Pacific Time (US & Canada)" )

time_zone_select( "user", 'time_zone', ActiveSupport::TimeZone.us_zones, default: "Pacific Time (US & Canada)")

time_zone_select( "user", 'time_zone', [ ActiveSupport::TimeZone['Alaska'], ActiveSupport::TimeZone['Hawaii'] ])

time_zone_select( "user", 'time_zone', /Australia/)

time_zone_select( "user", "time_zone", ActiveSupport::TimeZone.all.sort, model: ActiveSupport::TimeZone)


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# File 'lib/action_view/helpers/form_options_helper.rb', line 290

def time_zone_select(object, method, priority_zones = nil, options = {}, html_options = {})
  Tags::TimeZoneSelect.new(object, method, self, priority_zones, options, html_options).render
end